1/////////////////////////////////////////////////////////////////////////////// 2// 3// Copyright (c) 2015 Microsoft Corporation. All rights reserved. 4// 5// This code is licensed under the MIT License (MIT). 6// 7// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 8// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 9// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 10// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 11// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 12// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 13// THE SOFTWARE. 14// 15/////////////////////////////////////////////////////////////////////////////// 16 17#pragma once 18 19#ifndef GSL_STRING_SPAN_H 20#define GSL_STRING_SPAN_H 21 22#include <gsl/gsl_assert> 23#include <gsl/gsl_util> 24#include <gsl/span> 25 26#include <cstdint> 27#include <cstring> 28#include <string> 29 30#ifdef _MSC_VER 31#pragma warning(push) 32 33// blanket turn off warnings from CppCoreCheck for now 34// so people aren't annoyed by them when running the tool. 35// more targeted suppressions will be added in a future update to the GSL 36#pragma warning(disable : 26481 26482 26483 26485 26490 26491 26492 26493 26495) 37 38#if _MSC_VER < 1910 39#pragma push_macro("constexpr") 40#define constexpr /*constexpr*/ 41 42#endif // _MSC_VER < 1910 43#endif // _MSC_VER 44 45// In order to test the library, we need it to throw exceptions that we can catch 46#ifdef GSL_THROW_ON_CONTRACT_VIOLATION 47#define GSL_NOEXCEPT /*noexcept*/ 48#else 49#define GSL_NOEXCEPT noexcept 50#endif // GSL_THROW_ON_CONTRACT_VIOLATION 51 52namespace gsl 53{ 54// 55// czstring and wzstring 56// 57// These are "tag" typedefs for C-style strings (i.e. null-terminated character arrays) 58// that allow static analysis to help find bugs. 59// 60// There are no additional features/semantics that we can find a way to add inside the 61// type system for these types that will not either incur significant runtime costs or 62// (sometimes needlessly) break existing programs when introduced. 63// 64 65template <typename CharT, std::ptrdiff_t Extent = dynamic_extent> 66using basic_zstring = CharT*; 67 68template <std::ptrdiff_t Extent = dynamic_extent> 69using czstring = basic_zstring<const char, Extent>; 70 71template <std::ptrdiff_t Extent = dynamic_extent> 72using cwzstring = basic_zstring<const wchar_t, Extent>; 73 74template <std::ptrdiff_t Extent = dynamic_extent> 75using zstring = basic_zstring<char, Extent>; 76 77template <std::ptrdiff_t Extent = dynamic_extent> 78using wzstring = basic_zstring<wchar_t, Extent>; 79 80namespace details 81{ 82 inline std::ptrdiff_t string_length(const char* str, std::ptrdiff_t n) 83 { 84 if (str == nullptr || n <= 0) return 0; 85 86 span<const char> str_span{str, n}; 87 88 std::ptrdiff_t len = 0; 89 while (len < n && str_span[len]) len++; 90 91 return len; 92 } 93 94 inline std::ptrdiff_t wstring_length(const wchar_t* str, std::ptrdiff_t n) 95 { 96 if (str == nullptr || n <= 0) return 0; 97 98 span<const wchar_t> str_span{str, n}; 99 100 std::ptrdiff_t len = 0; 101 while (len < n && str_span[len]) len++; 102 103 return len; 104 } 105} 106 107// 108// ensure_sentinel() 109// 110// Provides a way to obtain an span from a contiguous sequence 111// that ends with a (non-inclusive) sentinel value. 112// 113// Will fail-fast if sentinel cannot be found before max elements are examined. 114// 115template <typename T, const T Sentinel> 116span<T, dynamic_extent> ensure_sentinel(T* seq, std::ptrdiff_t max = PTRDIFF_MAX) 117{ 118 auto cur = seq; 119 while ((cur - seq) < max && *cur != Sentinel) ++cur; 120 Ensures(*cur == Sentinel); 121 return {seq, cur - seq}; 122} 123 124// 125// ensure_z - creates a span for a czstring or cwzstring. 126// Will fail fast if a null-terminator cannot be found before 127// the limit of size_type. 128// 129template <typename T> 130inline span<T, dynamic_extent> ensure_z(T* const& sz, std::ptrdiff_t max = PTRDIFF_MAX) 131{ 132 return ensure_sentinel<T, 0>(sz, max); 133} 134 135// TODO (neilmac) there is probably a better template-magic way to get the const and non-const 136// overloads to share an implementation 137inline span<char, dynamic_extent> ensure_z(char* const& sz, std::ptrdiff_t max) 138{ 139 auto len = details::string_length(sz, max); 140 Ensures(sz[len] == 0); 141 return {sz, len}; 142} 143 144inline span<const char, dynamic_extent> ensure_z(const char* const& sz, std::ptrdiff_t max) 145{ 146 auto len = details::string_length(sz, max); 147 Ensures(sz[len] == 0); 148 return {sz, len}; 149} 150 151inline span<wchar_t, dynamic_extent> ensure_z(wchar_t* const& sz, std::ptrdiff_t max) 152{ 153 auto len = details::wstring_length(sz, max); 154 Ensures(sz[len] == 0); 155 return {sz, len}; 156} 157 158inline span<const wchar_t, dynamic_extent> ensure_z(const wchar_t* const& sz, std::ptrdiff_t max) 159{ 160 auto len = details::wstring_length(sz, max); 161 Ensures(sz[len] == 0); 162 return {sz, len}; 163} 164 165template <typename T, std::size_t N> 166span<T, dynamic_extent> ensure_z(T (&sz)[N]) 167{ 168 return ensure_z(&sz[0], static_cast<std::ptrdiff_t>(N)); 169} 170 171template <class Cont> 172span<typename std::remove_pointer<typename Cont::pointer>::type, dynamic_extent> 173ensure_z(Cont& cont) 174{ 175 return ensure_z(cont.data(), static_cast<std::ptrdiff_t>(cont.length())); 176} 177 178template <typename CharT, std::ptrdiff_t> 179class basic_string_span; 180 181namespace details 182{ 183 template <typename T> 184 struct is_basic_string_span_oracle : std::false_type 185 { 186 }; 187 188 template <typename CharT, std::ptrdiff_t Extent> 189 struct is_basic_string_span_oracle<basic_string_span<CharT, Extent>> : std::true_type 190 { 191 }; 192 193 template <typename T> 194 struct is_basic_string_span : is_basic_string_span_oracle<std::remove_cv_t<T>> 195 { 196 }; 197 198 template <typename T> 199 struct length_func 200 { 201 }; 202 203 template <> 204 struct length_func<char> 205 { 206 std::ptrdiff_t operator()(const char* const ptr, std::ptrdiff_t length) GSL_NOEXCEPT 207 { 208 return details::string_length(ptr, length); 209 } 210 }; 211 212 template <> 213 struct length_func<wchar_t> 214 { 215 std::ptrdiff_t operator()(const wchar_t* const ptr, std::ptrdiff_t length) GSL_NOEXCEPT 216 { 217 return details::wstring_length(ptr, length); 218 } 219 }; 220 221 template <> 222 struct length_func<const char> 223 { 224 std::ptrdiff_t operator()(const char* const ptr, std::ptrdiff_t length) GSL_NOEXCEPT 225 { 226 return details::string_length(ptr, length); 227 } 228 }; 229 230 template <> 231 struct length_func<const wchar_t> 232 { 233 std::ptrdiff_t operator()(const wchar_t* const ptr, std::ptrdiff_t length) GSL_NOEXCEPT 234 { 235 return details::wstring_length(ptr, length); 236 } 237 }; 238} 239 240// 241// string_span and relatives 242// 243template <typename CharT, std::ptrdiff_t Extent = dynamic_extent> 244class basic_string_span 245{ 246public: 247 using element_type = CharT; 248 using pointer = std::add_pointer_t<element_type>; 249 using reference = std::add_lvalue_reference_t<element_type>; 250 using const_reference = std::add_lvalue_reference_t<std::add_const_t<element_type>>; 251 using impl_type = span<element_type, Extent>; 252 253 using index_type = typename impl_type::index_type; 254 using iterator = typename impl_type::iterator; 255 using const_iterator = typename impl_type::const_iterator; 256 using reverse_iterator = typename impl_type::reverse_iterator; 257 using const_reverse_iterator = typename impl_type::const_reverse_iterator; 258 259 // default (empty) 260 constexpr basic_string_span() GSL_NOEXCEPT = default; 261 262 // copy 263 constexpr basic_string_span(const basic_string_span& other) GSL_NOEXCEPT = default; 264 265// move 266 constexpr basic_string_span(basic_string_span&& other) GSL_NOEXCEPT = default; 267 268 // assign 269 constexpr basic_string_span& operator=(const basic_string_span& other) GSL_NOEXCEPT = default; 270 271// move assign 272 constexpr basic_string_span& operator=(basic_string_span&& other) GSL_NOEXCEPT = default; 273 274 // from nullptr 275 constexpr basic_string_span(std::nullptr_t ptr) GSL_NOEXCEPT : span_(ptr) {} 276 277 constexpr basic_string_span(pointer ptr, index_type length) : span_(ptr, length) {} 278 constexpr basic_string_span(pointer firstElem, pointer lastElem) : span_(firstElem, lastElem) {} 279 280 // From static arrays - if 0-terminated, remove 0 from the view 281 // All other containers allow 0s within the length, so we do not remove them 282 template <std::size_t N> 283 constexpr basic_string_span(element_type (&arr)[N]) : span_(remove_z(arr)) 284 { 285 } 286 287 template <std::size_t N, class ArrayElementType = std::remove_const_t<element_type>> 288 constexpr basic_string_span(std::array<ArrayElementType, N>& arr) GSL_NOEXCEPT : span_(arr) 289 { 290 } 291 292 template <std::size_t N, class ArrayElementType = std::remove_const_t<element_type>> 293 constexpr basic_string_span(const std::array<ArrayElementType, N>& arr) GSL_NOEXCEPT 294 : span_(arr) 295 { 296 } 297 298 // Container signature should work for basic_string after C++17 version exists 299 template <class Traits, class Allocator> 300 constexpr basic_string_span(std::basic_string<element_type, Traits, Allocator>& str) 301 : span_(&str[0], narrow_cast<std::ptrdiff_t>(str.length())) 302 { 303 } 304 305 template <class Traits, class Allocator> 306 constexpr basic_string_span(const std::basic_string<element_type, Traits, Allocator>& str) 307 : span_(&str[0], str.length()) 308 { 309 } 310 311 // from containers. Containers must have a pointer type and data() function signatures 312 template <class Container, 313 class = std::enable_if_t< 314 !details::is_basic_string_span<Container>::value && 315 std::is_convertible<typename Container::pointer, pointer>::value && 316 std::is_convertible<typename Container::pointer, 317 decltype(std::declval<Container>().data())>::value>> 318 constexpr basic_string_span(Container& cont) : span_(cont) 319 { 320 } 321 322 template <class Container, 323 class = std::enable_if_t< 324 !details::is_basic_string_span<Container>::value && 325 std::is_convertible<typename Container::pointer, pointer>::value && 326 std::is_convertible<typename Container::pointer, 327 decltype(std::declval<Container>().data())>::value>> 328 constexpr basic_string_span(const Container& cont) : span_(cont) 329 { 330 } 331 332 // from string_span 333 template < 334 class OtherValueType, std::ptrdiff_t OtherExtent, 335 class = std::enable_if_t<std::is_convertible< 336 typename basic_string_span<OtherValueType, OtherExtent>::impl_type, impl_type>::value>> 337 constexpr basic_string_span(basic_string_span<OtherValueType, OtherExtent> other) 338 : span_(other.data(), other.length()) 339 { 340 } 341 342 template <index_type Count> 343 constexpr basic_string_span<element_type, Count> first() const 344 { 345 return {span_.template first<Count>()}; 346 } 347 348 constexpr basic_string_span<element_type, dynamic_extent> first(index_type count) const 349 { 350 return {span_.first(count)}; 351 } 352 353 template <index_type Count> 354 constexpr basic_string_span<element_type, Count> last() const 355 { 356 return {span_.template last<Count>()}; 357 } 358 359 constexpr basic_string_span<element_type, dynamic_extent> last(index_type count) const 360 { 361 return {span_.last(count)}; 362 } 363 364 template <index_type Offset, index_type Count> 365 constexpr basic_string_span<element_type, Count> subspan() const 366 { 367 return {span_.template subspan<Offset, Count>()}; 368 } 369 370 constexpr basic_string_span<element_type, dynamic_extent> 371 subspan(index_type offset, index_type count = dynamic_extent) const 372 { 373 return {span_.subspan(offset, count)}; 374 } 375 376 constexpr reference operator[](index_type idx) const { return span_[idx]; } 377 constexpr reference operator()(index_type idx) const { return span_[idx]; } 378 379 constexpr pointer data() const { return span_.data(); } 380 381 constexpr index_type length() const GSL_NOEXCEPT { return span_.size(); } 382 constexpr index_type size() const GSL_NOEXCEPT { return span_.size(); } 383 constexpr index_type size_bytes() const GSL_NOEXCEPT { return span_.size_bytes(); } 384 constexpr index_type length_bytes() const GSL_NOEXCEPT { return span_.length_bytes(); } 385 constexpr bool empty() const GSL_NOEXCEPT { return size() == 0; } 386 387 constexpr iterator begin() const GSL_NOEXCEPT { return span_.begin(); } 388 constexpr iterator end() const GSL_NOEXCEPT { return span_.end(); } 389 390 constexpr const_iterator cbegin() const GSL_NOEXCEPT { return span_.cbegin(); } 391 constexpr const_iterator cend() const GSL_NOEXCEPT { return span_.cend(); } 392 393 constexpr reverse_iterator rbegin() const GSL_NOEXCEPT { return span_.rbegin(); } 394 constexpr reverse_iterator rend() const GSL_NOEXCEPT { return span_.rend(); } 395 396 constexpr const_reverse_iterator crbegin() const GSL_NOEXCEPT { return span_.crbegin(); } 397 constexpr const_reverse_iterator crend() const GSL_NOEXCEPT { return span_.crend(); } 398 399private: 400 static impl_type remove_z(pointer const& sz, std::ptrdiff_t max) 401 { 402 return {sz, details::length_func<element_type>()(sz, max)}; 403 } 404 405 template <std::size_t N> 406 static impl_type remove_z(element_type (&sz)[N]) 407 { 408 return remove_z(&sz[0], narrow_cast<std::ptrdiff_t>(N)); 409 } 410 411 impl_type span_; 412}; 413 414template <std::ptrdiff_t Extent = dynamic_extent> 415using string_span = basic_string_span<char, Extent>; 416 417template <std::ptrdiff_t Extent = dynamic_extent> 418using cstring_span = basic_string_span<const char, Extent>; 419 420template <std::ptrdiff_t Extent = dynamic_extent> 421using wstring_span = basic_string_span<wchar_t, Extent>; 422 423template <std::ptrdiff_t Extent = dynamic_extent> 424using cwstring_span = basic_string_span<const wchar_t, Extent>; 425 426// 427// to_string() allow (explicit) conversions from string_span to string 428// 429 430template <typename CharT, std::ptrdiff_t Extent> 431std::basic_string<typename std::remove_const<CharT>::type> 432to_string(basic_string_span<CharT, Extent> view) 433{ 434 return {view.data(), static_cast<std::size_t>(view.length())}; 435} 436 437template <typename CharT, typename Traits = typename std::char_traits<CharT>, 438 typename Allocator = std::allocator<CharT>, typename gCharT, std::ptrdiff_t Extent> 439std::basic_string<CharT, Traits, Allocator> to_basic_string(basic_string_span<gCharT, Extent> view) 440{ 441 return {view.data(), static_cast<std::size_t>(view.length())}; 442} 443 444// zero-terminated string span, used to convert 445// zero-terminated spans to legacy strings 446template <typename CharT, std::ptrdiff_t Extent = dynamic_extent> 447class basic_zstring_span 448{ 449public: 450 using value_type = CharT; 451 using const_value_type = std::add_const_t<CharT>; 452 453 using pointer = std::add_pointer_t<value_type>; 454 using const_pointer = std::add_pointer_t<const_value_type>; 455 456 using zstring_type = basic_zstring<value_type, Extent>; 457 using const_zstring_type = basic_zstring<const_value_type, Extent>; 458 459 using impl_type = span<value_type, Extent>; 460 using string_span_type = basic_string_span<value_type, Extent>; 461 462 constexpr basic_zstring_span(impl_type s) GSL_NOEXCEPT : span_(s) 463 { 464 // expects a zero-terminated span 465 Expects(s[s.size() - 1] == '\0'); 466 } 467 468 // copy 469 constexpr basic_zstring_span(const basic_zstring_span& other) = default; 470 471// move 472 constexpr basic_zstring_span(basic_zstring_span&& other) = default; 473 474 // assign 475 constexpr basic_zstring_span& operator=(const basic_zstring_span& other) = default; 476 477// move assign 478 constexpr basic_zstring_span& operator=(basic_zstring_span&& other) = default; 479 480 constexpr bool empty() const GSL_NOEXCEPT { return span_.size() == 0; } 481 482 constexpr string_span_type as_string_span() const GSL_NOEXCEPT 483 { 484 auto sz = span_.size(); 485 return span_.first(sz <= 0 ? 0 : sz - 1); 486 } 487 488 constexpr string_span_type ensure_z() const GSL_NOEXCEPT { return gsl::ensure_z(span_); } 489 490 constexpr const_zstring_type assume_z() const GSL_NOEXCEPT { return span_.data(); } 491 492private: 493 impl_type span_; 494}; 495 496template <std::ptrdiff_t Max = dynamic_extent> 497using zstring_span = basic_zstring_span<char, Max>; 498 499template <std::ptrdiff_t Max = dynamic_extent> 500using wzstring_span = basic_zstring_span<wchar_t, Max>; 501 502template <std::ptrdiff_t Max = dynamic_extent> 503using czstring_span = basic_zstring_span<const char, Max>; 504 505template <std::ptrdiff_t Max = dynamic_extent> 506using cwzstring_span = basic_zstring_span<const wchar_t, Max>; 507 508// operator == 509template <class CharT, std::ptrdiff_t Extent, class T, 510 class = std::enable_if_t< 511 details::is_basic_string_span<T>::value || 512 std::is_convertible<T, gsl::basic_string_span<std::add_const_t<CharT>>>::value>> 513bool operator==(const gsl::basic_string_span<CharT, Extent>& one, const T& other) GSL_NOEXCEPT 514{ 515 const gsl::basic_string_span<std::add_const_t<CharT>> tmp(other); 516 return std::equal(one.begin(), one.end(), tmp.begin(), tmp.end()); 517} 518 519template <class CharT, std::ptrdiff_t Extent, class T, 520 class = std::enable_if_t< 521 !details::is_basic_string_span<T>::value && 522 std::is_convertible<T, gsl::basic_string_span<std::add_const_t<CharT>>>::value>> 523bool operator==(const T& one, const gsl::basic_string_span<CharT, Extent>& other) GSL_NOEXCEPT 524{ 525 gsl::basic_string_span<std::add_const_t<CharT>> tmp(one); 526 return std::equal(tmp.begin(), tmp.end(), other.begin(), other.end()); 527} 528 529// operator != 530template <typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T, 531 typename = std::enable_if_t<std::is_convertible< 532 T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value>> 533bool operator!=(gsl::basic_string_span<CharT, Extent> one, const T& other) GSL_NOEXCEPT 534{ 535 return !(one == other); 536} 537 538template < 539 typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T, 540 typename Dummy = std::enable_if_t< 541 std::is_convertible<T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value && 542 !gsl::details::is_basic_string_span<T>::value>> 543bool operator!=(const T& one, gsl::basic_string_span<CharT, Extent> other) GSL_NOEXCEPT 544{ 545 return !(one == other); 546} 547 548// operator< 549template <typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T, 550 typename = std::enable_if_t<std::is_convertible< 551 T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value>> 552bool operator<(gsl::basic_string_span<CharT, Extent> one, const T& other) GSL_NOEXCEPT 553{ 554 const gsl::basic_string_span<std::add_const_t<CharT>, Extent> tmp(other); 555 return std::lexicographical_compare(one.begin(), one.end(), tmp.begin(), tmp.end()); 556} 557 558template < 559 typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T, 560 typename Dummy = std::enable_if_t< 561 std::is_convertible<T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value && 562 !gsl::details::is_basic_string_span<T>::value>> 563bool operator<(const T& one, gsl::basic_string_span<CharT, Extent> other) GSL_NOEXCEPT 564{ 565 gsl::basic_string_span<std::add_const_t<CharT>, Extent> tmp(one); 566 return std::lexicographical_compare(tmp.begin(), tmp.end(), other.begin(), other.end()); 567} 568 569#ifndef _MSC_VER 570 571// VS treats temp and const containers as convertible to basic_string_span, 572// so the cases below are already covered by the previous operators 573 574template < 575 typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T, 576 typename DataType = typename T::value_type, 577 typename Dummy = std::enable_if_t< 578 !gsl::details::is_span<T>::value && !gsl::details::is_basic_string_span<T>::value && 579 std::is_convertible<DataType*, CharT*>::value && 580 std::is_same<std::decay_t<decltype(std::declval<T>().size(), *std::declval<T>().data())>, 581 DataType>::value>> 582bool operator<(gsl::basic_string_span<CharT, Extent> one, const T& other) GSL_NOEXCEPT 583{ 584 gsl::basic_string_span<std::add_const_t<CharT>, Extent> tmp(other); 585 return std::lexicographical_compare(one.begin(), one.end(), tmp.begin(), tmp.end()); 586} 587 588template < 589 typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T, 590 typename DataType = typename T::value_type, 591 typename Dummy = std::enable_if_t< 592 !gsl::details::is_span<T>::value && !gsl::details::is_basic_string_span<T>::value && 593 std::is_convertible<DataType*, CharT*>::value && 594 std::is_same<std::decay_t<decltype(std::declval<T>().size(), *std::declval<T>().data())>, 595 DataType>::value>> 596bool operator<(const T& one, gsl::basic_string_span<CharT, Extent> other) GSL_NOEXCEPT 597{ 598 gsl::basic_string_span<std::add_const_t<CharT>, Extent> tmp(one); 599 return std::lexicographical_compare(tmp.begin(), tmp.end(), other.begin(), other.end()); 600} 601#endif 602 603// operator <= 604template <typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T, 605 typename = std::enable_if_t<std::is_convertible< 606 T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value>> 607bool operator<=(gsl::basic_string_span<CharT, Extent> one, const T& other) GSL_NOEXCEPT 608{ 609 return !(other < one); 610} 611 612template < 613 typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T, 614 typename Dummy = std::enable_if_t< 615 std::is_convertible<T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value && 616 !gsl::details::is_basic_string_span<T>::value>> 617bool operator<=(const T& one, gsl::basic_string_span<CharT, Extent> other) GSL_NOEXCEPT 618{ 619 return !(other < one); 620} 621 622#ifndef _MSC_VER 623 624// VS treats temp and const containers as convertible to basic_string_span, 625// so the cases below are already covered by the previous operators 626 627template < 628 typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T, 629 typename DataType = typename T::value_type, 630 typename Dummy = std::enable_if_t< 631 !gsl::details::is_span<T>::value && !gsl::details::is_basic_string_span<T>::value && 632 std::is_convertible<DataType*, CharT*>::value && 633 std::is_same<std::decay_t<decltype(std::declval<T>().size(), *std::declval<T>().data())>, 634 DataType>::value>> 635bool operator<=(gsl::basic_string_span<CharT, Extent> one, const T& other) GSL_NOEXCEPT 636{ 637 return !(other < one); 638} 639 640template < 641 typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T, 642 typename DataType = typename T::value_type, 643 typename Dummy = std::enable_if_t< 644 !gsl::details::is_span<T>::value && !gsl::details::is_basic_string_span<T>::value && 645 std::is_convertible<DataType*, CharT*>::value && 646 std::is_same<std::decay_t<decltype(std::declval<T>().size(), *std::declval<T>().data())>, 647 DataType>::value>> 648bool operator<=(const T& one, gsl::basic_string_span<CharT, Extent> other) GSL_NOEXCEPT 649{ 650 return !(other < one); 651} 652#endif 653 654// operator> 655template <typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T, 656 typename = std::enable_if_t<std::is_convertible< 657 T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value>> 658bool operator>(gsl::basic_string_span<CharT, Extent> one, const T& other) GSL_NOEXCEPT 659{ 660 return other < one; 661} 662 663template < 664 typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T, 665 typename Dummy = std::enable_if_t< 666 std::is_convertible<T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value && 667 !gsl::details::is_basic_string_span<T>::value>> 668bool operator>(const T& one, gsl::basic_string_span<CharT, Extent> other) GSL_NOEXCEPT 669{ 670 return other < one; 671} 672 673#ifndef _MSC_VER 674 675// VS treats temp and const containers as convertible to basic_string_span, 676// so the cases below are already covered by the previous operators 677 678template < 679 typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T, 680 typename DataType = typename T::value_type, 681 typename Dummy = std::enable_if_t< 682 !gsl::details::is_span<T>::value && !gsl::details::is_basic_string_span<T>::value && 683 std::is_convertible<DataType*, CharT*>::value && 684 std::is_same<std::decay_t<decltype(std::declval<T>().size(), *std::declval<T>().data())>, 685 DataType>::value>> 686bool operator>(gsl::basic_string_span<CharT, Extent> one, const T& other) GSL_NOEXCEPT 687{ 688 return other < one; 689} 690 691template < 692 typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T, 693 typename DataType = typename T::value_type, 694 typename Dummy = std::enable_if_t< 695 !gsl::details::is_span<T>::value && !gsl::details::is_basic_string_span<T>::value && 696 std::is_convertible<DataType*, CharT*>::value && 697 std::is_same<std::decay_t<decltype(std::declval<T>().size(), *std::declval<T>().data())>, 698 DataType>::value>> 699bool operator>(const T& one, gsl::basic_string_span<CharT, Extent> other) GSL_NOEXCEPT 700{ 701 return other < one; 702} 703#endif 704 705// operator >= 706template <typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T, 707 typename = std::enable_if_t<std::is_convertible< 708 T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value>> 709bool operator>=(gsl::basic_string_span<CharT, Extent> one, const T& other) GSL_NOEXCEPT 710{ 711 return !(one < other); 712} 713 714template < 715 typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T, 716 typename Dummy = std::enable_if_t< 717 std::is_convertible<T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value && 718 !gsl::details::is_basic_string_span<T>::value>> 719bool operator>=(const T& one, gsl::basic_string_span<CharT, Extent> other) GSL_NOEXCEPT 720{ 721 return !(one < other); 722} 723 724#ifndef _MSC_VER 725 726// VS treats temp and const containers as convertible to basic_string_span, 727// so the cases below are already covered by the previous operators 728 729template < 730 typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T, 731 typename DataType = typename T::value_type, 732 typename Dummy = std::enable_if_t< 733 !gsl::details::is_span<T>::value && !gsl::details::is_basic_string_span<T>::value && 734 std::is_convertible<DataType*, CharT*>::value && 735 std::is_same<std::decay_t<decltype(std::declval<T>().size(), *std::declval<T>().data())>, 736 DataType>::value>> 737bool operator>=(gsl::basic_string_span<CharT, Extent> one, const T& other) GSL_NOEXCEPT 738{ 739 return !(one < other); 740} 741 742template < 743 typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T, 744 typename DataType = typename T::value_type, 745 typename Dummy = std::enable_if_t< 746 !gsl::details::is_span<T>::value && !gsl::details::is_basic_string_span<T>::value && 747 std::is_convertible<DataType*, CharT*>::value && 748 std::is_same<std::decay_t<decltype(std::declval<T>().size(), *std::declval<T>().data())>, 749 DataType>::value>> 750bool operator>=(const T& one, gsl::basic_string_span<CharT, Extent> other) GSL_NOEXCEPT 751{ 752 return !(one < other); 753} 754#endif 755} // namespace GSL 756 757#undef GSL_NOEXCEPT 758 759#ifdef _MSC_VER 760#pragma warning(pop) 761 762#if _MSC_VER < 1910 763#undef constexpr 764#pragma pop_macro("constexpr") 765 766#endif // _MSC_VER < 1910 767#endif // _MSC_VER 768 769#endif // GSL_STRING_SPAN_H 770